Nr2e1 deficiency aggravates insulin resistance and chronic inflammation of visceral adipose tissues in a diet-induced obese mice model

Life Sci. 2021 Aug 1:278:119562. doi: 10.1016/j.lfs.2021.119562. Epub 2021 Apr 26.

Abstract

Aims: To investigate the nuclear receptor subfamily 2 group E member 1 (Nr2e1) expression in adipose tissues of obese mice and assess the role of Nr2e1 in insulin resistance and chronic inflammation of the adipose tissues.

Main methods: An obese model was established in Nr2e1 knockout (KO) mice and their wild type (WT) littermates through a long-term high-fat diet (HFD) feeding regime. The epididymal fat weight, body weight, and daily food intake were recorded. The blood lipid profile, blood inflammatory factors, and the levels of fasting blood glucose (FBG) and fasting insulin were determined. We estimated insulin resistance by the homeostasis model assessment (HOMA). The expression of inflammatory factors and F4/80 was examined by polymerase chain reaction (PCR) and western blotting to assess adipose tissues inflammation. We also determined the molecules of insulin signaling and the nuclear factor kappa B (NF-κB) pathway by western blotting.

Key findings: The Nr2e1 expression was upregulated in WT obese mice when compared with that in control mice. Despite a lower body weight and epididymal fat mass in Nr2e1-/- mice, these rats showed increased inflammatory cytokines secretion, more pronounced hyperlipidemia, and impaired insulin sensitivity after HFD treatment. Further investigation revealed that Nr2e1 deletion affected the expression of insulin signaling and NF-κB pathway-related molecules in visceral adipose tissues.

Significance: Nr2e1 may act as a potential target to improve insulin sensitivity and inflammation in obesity and related complications.

Keywords: Chronic inflammation; Epididymal adipose tissue; Insulin resistance; Nr2e1; Obesity.

MeSH terms

  • Animal Feed
  • Animals
  • Blood Glucose / metabolism
  • Body Weight
  • Chronic Disease
  • Crosses, Genetic
  • Disease Models, Animal
  • Glucose Intolerance
  • Glucose Tolerance Test
  • Homeostasis
  • Hyperlipidemias / metabolism
  • Inflammation
  • Insulin / metabolism
  • Insulin Resistance*
  • Intra-Abdominal Fat / metabolism*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • NF-kappa B p50 Subunit / metabolism
  • Obesity / metabolism
  • Receptors, Cytoplasmic and Nuclear / metabolism*
  • Signal Transduction

Substances

  • Blood Glucose
  • Insulin
  • NF-kappa B p50 Subunit
  • Nr2e1 protein, mouse
  • Receptors, Cytoplasmic and Nuclear
  • Nfkb1 protein, mouse